The prior art has long testified to the need for a dental device which would serve to readily withdraw or expand the lips and cheeks and retract the tongue from their normal position in order to facilitate both a visual and physical access to the teeth as well as to other anatomical areas such as the gingivae surrounding the teeth and the palate and throat, and simultaneously aid him to maintain a clean, dry field of operation without the assistance of an auxiliary person.
The prior art in the present area is represented by such patents as U.S. Pat. No. 2,535,005 (1950) to Wiprud and U.S. Pat. No. 3,916,880 (1975) to Schroer. The devices of said patents, as well as others known in the art, have been found to be awkward of use, in most instances requiring an assistant to hold the instrument in place, and also to involve discomforture on the part of the patient. In addition, certain sterilization problems have attended the use of various prior devices including that of the patent to Schroer. Further, prior devices of the present class have been found to be somewhat difficult to manufacture and, accordingly, have been relatively expensive items for the practitioner to purchase.
In light of the above, it may be appreciated that the present invention comprises an effort to provide a simplified mechanical means of lip, cheek and tongue retention that will be both convenient for use by the dentist and comfortable for the patient, and eliminating the services of an assistant who may now be free to perform other essential duties.